Studies; Reprints Volume 41

Description

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1922 edition. Excerpt: ...not reduce Fehling's solution until after hydrolysis with acid. For analysis the substance was dried to constant weight under diminished pressure at the temperature of water vapor. 0.1133 gm. of substance gave on combustion 0.1331 gm. of CO1 and 0.0482 gm. Of H30. 0.0923 gm. of substance gave 0.0341 gm. of BaSO4. 0.2770 " " " " 0.0625 " " MgcentsP, O;. This substance is obtained by the action of phosphorus oxychloride on diacetone glucose when the temperature of the reaction mixture is allowed to rise above +10 during the process of destroying the unutilized phosphorus oxychloride. 10 gm. of dried diacetone glucose are dissolved in 50 cc. of dry pyridine and cooled to---20. To this is added 5.4 gm. of phosphorus oxychloride dissolved in 20 cc. of pyridine also cooled to--20. The mixture is allowed to remain at--20 for several hours and then 20 cc. of ice cold water are added. The temperature of the mixture rises to about +30. After allowing it to stand at room temperature for a while it is further diluted with water. An excess of barium hydrate is added and the pyridine removed by distillation under diminished pressure. The product is treated with silver sulfate and barium hydrate as previously described. The final residue is soluble in water which on the addition of alcohol forms a gelatinous mass. The barium salt is precipitated from its aqueous solution by pouring it into a large volume of dry acetone. The salt is obtained as a fine white powder. It does not reduce Fehling's solution until after hydrolysis with acid. For analysis the substance was dried under diminished pressure at the temperature of water vapor. 1-2-Monoacetone Phosphoric Acid Glucoside from M onoacetone Glucose. 10 gmshow more